Process of brazing tubing.



H. HIGGIN.

PROCESS OF BRAZING TUBING.

APPLICATION FILED MAR.14,1910.

1,052,820, Patented Feb. 11, 1913.

x g g I L memes es i To all whom, it may concern:

I ED STATES PATENT OFFICE.

HENRY HIGGIN, .OF NEWPORT, KENTUCKY, ASSIGNOR To THE HIGGIN MANUFACTUR- ING COMPANY, OF NEWPORT, KENTUCKY, A CORPORATION pr WEST VIRGINIA.

' PROCESS OF E AZT GTUEING.

Application filed March 14, 1910. Serial No. 549,301.

Be it known that I,HENRY HIGGIN, a citizen of the United States, and a residentof the city of New-port, in the county of Campbell and State of Kentucky, have invented certain new and useful Improvements in Processes of Brazing Tubing, of which the following is a full, clear, and exact description,

. reference being had to the accompanying drawing, forming a part of this specification.

In the process of the manufacture of brass tubing and the like provided with'a longitudinal seam, great difficulty is experienced and-heavy loss incurred in solderingorrbrazing the seam so-that there shall be no parting at the joint. Such seamed tubes are usually manufactured from sheets of brass or the-likecut into strips of uniform width to make a' tube of the desired diameter, and

, the tube isaforniedby running the strip between dies graded in shape to gradually fold the strip into a tube. into cylindrical shape" is very prone totshow irregularity at the seam; the edges, in

places, overlap, and at other places gap apart. Now when the unfinished tube is placed in the brazing furnace and heated to brazing temperature, with the tube supported only at the edge of the furnace and ex posed to the heat, betweenbearings eighteen inches to twenty-four inches apart, as'is usually the case, whether the brazed seam will hold, and the loss from defective joints is vefy large. I

have discovered, however, that such tubing may be very successfully welded or brazed electrically, with a percentage of loss from open joints practically negli gible, especially.

where the tubing has been accurately folded from the strip.

In the drawings I have illustrated suitable apparatus for carrying out my process.

Figure l'is a perspective view of a brazing machine with the tubing in place. Fig. 2 is a front elevation partly in vertical section. Fig. 3 is a perspective View of a section of the tubing.

1 is the base plate of any convenient size and, shape for holding the operative parts.

of the apparatus.

Bolted on the base a. plate 2 provided with a longitudinal dovetailed recess 3 in which is adjustably mounted the block 4. A corresponding block 5 is securely bolted in Tubing thus folded itis almost a matter of luck fixed position on the plate 2. The block is provided with a socket 6 in which is Patented Feb. 11, 1913.

mounted the pin. 7, Screw threaded in the block at the base of the socket. This 'pin passes through the stop plate 8 which is bolted on the plate 2 and the pin is provided with a knurled head 9, while a coiled spring 10 mounted. on the pin 7 bears between the base of the socket 6 and the stop plate 8, so that nor mally the block'4 is .un-

der tension pressing it toward the fixed block 5. The head 9 of the pin 7, however, by contact withthe stop plate 8 limits this tension.

. Mounted on spindles 11, secured to the upper surface of the blocks l and 5, are the metallic rollers 12, 12, provided with corre sponding grooves 13, 13, to fitaround and properly embrace the tubing 14, whose edges are to be brazed, and it will be evident from the foregoing description that the edges of the tubing will be pressed and held' uniformly together as the tubing is fed con-, tinuously between these rollers. i

I have not illustrated any mechanism for feeding the tube continuously between the rollers, as the brazing apparatus may be attached to the machine for forming the'tubes and the" same mechanism employed to propel the blank through the tube forming machine may be used to propel the tube through the brazing apparatus; or the tubes after being formed and removed from the machine may be introduced into the brazing apparatus and drawn or pushed between the rollers by any of the well known appliances for that purpose.

15, 16 are the wires for conveying the electric current wires are properly insulated and connected. by any suitable connection as 17 V with the rollers 12, 12, one wire to one roller and the other tothe other roller. 1

I 18 is the switch for throwing on or off the current, which as usual in will be of great volume but of low voltage.

Before the tube is introduced between the rollers, a narrow strip of spelter solder 19 is introduced between the edges of the tube, or the tube may have the outer edges cut to the machine, and these 7 Welding machines away atthe joint to form a V-shaped cut in cross section. Where the V-shaped cut is provided instead of a spelter strip, grain spelter mixed with powdered ,flux andreduced to the consistency of a thick cream may be used, as is common practice in brazing tubes. The tube is then fed slowly between the rolls 12, 12, with the seam uppermost, the current is turned on and at the "the rolls together, and the tube is brazed or soldered joint the temperature quickly rises to the brazing point, the spring pressure between presses the edges of the joint firmly with a perfect joint, not at all liable to open up, or become distorted. 7

What I claim as new and of my inven tion and desire to secure by Letters Patent, is i 1. The method of brazing tubing which consists in applying uniform lateral pres sure around the tube on both sidesof the seam by lateral pressure devices, simultaneously feeding forward the: tube and passing an electric current from one lateral pressure device to the other of suflicient intensity to distribute the heat uniformly through the taneously feeding forward the tube and passing an electric current from one lateral pressure device to the other of sufficient intensity to distribute the heat uniformly through the tube and to raise the temperature of the tube at the seam to the brazing temperature without melting the material of the tube.

HENRY HIGGIN. Witnesses:

FRANK KUNKEL, 2K. SMITH. 

